Field of the Invention
The present invention relates to a method for manufacturing a polymer compound.
Description of Related Art
In lithographic techniques, for example, a step of forming a resist pattern in a predetermined form on a resist film is performed by forming a resist film which is formed of a resist material on a substrate, selectively exposing the resist film via a mask on which a predetermined pattern is formed to radioactive rays such as light or electron beams, and carrying out a development process thereon.
A resist material in which an exposed portion changes to have a characteristic of being dissolved in a developing solution is called a positive type material and a resist material in which an exposed portion changes to have a characteristic of not being dissolved in a developing solution is called a negative type material.
In recent years, pattern refinement in the manufacturing of semiconductor elements or liquid crystal display elements has rapidly progressed due to the development of lithographic techniques.
As a refinement method, the wavelength of the exposure light source is generally shortened (the energy is increased).
In detail, ultraviolet rays which are represented by g-line and i-line are used in the prior art; however, currently, the mass production of semiconductor elements using KrF excimer lasers or ArF excimer lasers has started. In addition, research is also being undertaken into electron beams, extreme ultra violet rays (EUV), X-rays, or the like which have a shorter wavelength (higher energy) than these excimer lasers.
Lithographic characteristics such as sensitivity with respect to these exposure light source and resolution which is able to reproduce a pattern with fine dimensions are required for resist material.
As a resist material which satisfies these demands, a chemical amplification type resist composition which contains an acid generating agent component which generates an acid upon exposure to light and a base material component of which the solubility with respect to a developing solution changes due to the effect of the acid is used in the prior art.
A resin (a base resin) is generally used as the base material component which is used in the chemical amplification type resist composition.
For example, as a chemical amplification type resist composition for forming a positive type resist pattern in an alkali development process which uses an alkali developing solution as a developing solution, a composition which contains an acid generating agent component and a resin component of which the solubility with respect to an alkali developing solution increases due to the effect of the acid is generally used. Regarding the resist film which is formed using the resist composition, when performing selective exposure at the time of resist pattern forming, an acid is generated from an acid generating agent component in an exposed portion, the solubility with respect to an alkali developing solution of a resin component increases due to the effect of the acid, and the exposed portion is soluble with respect to the alkali developing solution. For this reason, carrying out the alkali development forms a positive type pattern in which a non-exposed portion remains as a pattern.
As the resin component, a component where the polarity of the resin increases due to the effect of the acid is generally used. When the polarity increases, the solubility with respect to the alkali developing solution increases, but the solubility with respect to the organic solvent decreases. Therefore, when applying a solvent development process which uses a developing solution (an organic type developing solution) which includes an organic solvent instead of an alkali development process, since the solubility with respect to an organic type developing solution is relatively decreased in the exposed portion, in the solvent development process, a non-exposed portion of a resist film is dissolved and removed by an organic type developing solution to form a negative type resist pattern where an exposed portion remains as a pattern. A solvent development process which forms a negative type resist pattern in this manner may be called a negative type development process (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2009-25707).
Currently, as a base resin of a resist composition which is used in ArF excimer laser lithography or the like, a resin (an acryl-based resin) which has a constituent unit which is derived from (meth)acrylic acid ester in the main chain or the like is generally used since the transparency in the vicinity of 193 nm is excellent (for example, refer to Japanese Unexamined Patent Application, First Publication No. 2003-241385).